State: OK To Restart Digging Of Tunnel Access Pit

SEATTLE (AP) – State transportation officials gave Seattle Tunnel Partners the OK on Tuesday to resume excavation on a pit being dug to reach and repair Bertha, the broken tunneling machine.

But officials still don’t know whether the recently discovered ground settlement was caused by all the water being drained from under the pit, according to Alaskan Way Viaduct Replacement project spokeswoman Laura Newborn. Workers have been “de-watering” to reduce pressure from underneath and on the sides of the hole.

Digging was stopped last week after monitoring systems detected 1 inch to 1.4 inch of ground settlement near the pit – under a section of the State Route 99 viaduct and buildings in historic Pioneer Square. No significant sinking has occurred since Dec. 5 so they said the digging can resume, she said.

Gov. Jay Inslee, speaking after a transportation press conference in Medina, said he was confident that the…